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Irish1941 11-27-2017 11:53 PM

Frame pulling experts
 
Friend has a '88 full size Blazer and the front spring hanger is 1" forward.
Somewhere in a past life it got bent.
Wheelbase is off almost dead on 1" on drivers side.
Measured it six ways from Sunday and can only find that the front horn has gone forward. The rear shackles on RH are near vertical and LH side are leaning forward!
Spring at 47" long both sides.
Took it to one frame shop. Take it in for an alignment they said
Toe was out an 1". No kidding seeing axle is forward an 1".
Back to frame shop
They sent it up on their laser machine and come back and say it's wore out bushings.
How can that be if LH shackle is clearly not vertical like RH side?
I show them the stationary front LH hanger is forward an 1" from RH with straight edge across. Nope. Its worn bushings... I guess worn spring bushings can physically move the RIVETED hanger forward an 1" !
ARRGGGG!
$300 wasted and the hanger is still forward 1"
Any idea suggestions on best way tackle this beside drive it in a large stationary object?

MARTINSR 11-28-2017 12:01 AM

Re: Frame pulling experts
 
The description is a little tough for me to grasp but it sounds like you need a real frame shop. The only way that rear shackle could be leaning forward is if the frame is bent making it shorter from the front perch to the rear, OR if the bracket for the front perch is bent back somehow. Measure from the center of the spring bolt on both sides up to a "control point" which would be most any hole in the frame or rivet for a cross member or something like that to find out if that is what is rear ward.

Here is a "Basics of Basics" for measuring something like that. http://67-72chevytrucks.com/vboard/s...d.php?t=639860

Brian

Irish1941 11-28-2017 01:07 PM

Re: Frame pulling experts
 
Thanks for reply, Brian.
Guess I was maybe a bit vague
The wheelbase is 106.5 on passenger side, which is correct.
LH side is 107.5
Both front springs are 47"

Center line from axle to eye of front spring hanger is
RH 23 1/8"
LH 23 1/8"
Springs equal on the axle.

Axle center to front spring rear shackle upper bolt.
RH 23 1/2"
LH 24 3/8"

This leads me to the conclusion it's bent up and pulled forward in the front part of the LH rail causing spring to come forward.
You can physically see the difference in the tire to fender clearances.
The sheet metal is all straight and cowl to rad support measure equal both sides.
Engine is square in the rails as is the crossmember.
I'll add a photo or two if I get a chance.

I was thinking a big truck shop because the body shop insurance factories around here can't seem to grasp the problem.

MARTINSR 11-28-2017 02:37 PM

Re: Frame pulling experts
 
Ok, somehow I thought we went to the back of the truck. Ok, what that sounds like is the front horn hit something and bent the frame up over the axle.


Brian

scott123 11-29-2017 08:55 PM

Re: Frame pulling experts
 
Check the axle perch as well. In some crashes the pin will sheer off and the axle will move forward or backward. The U-bolts will hold the leaf springs in tact.

I have one outside now that got hit hard in the left front wheel. Blazer drove good and did not wear tires at all. I never knew it until we pulled the body. The crash was visible to the eye.

S

Irish1941 11-30-2017 07:01 PM

Re: Frame pulling experts
 
Was hoping it was just the pin when I first heard about it...
Axle would have just slid up the leaf. Easy fix. No luck this time
Frame front has a tweak for sure. Cant post pix due to photobucket changes but
to try and explain it...

RH front hanger to rear shackle vs LH side.
O_________________l


O_________________/

Cowl is square as is the rear axle.

The front frame horn where the hanger is mounted has moved up, flattening out the curve and moving entire LH spring and axle forward on LH side.
I'm think it needs to be pulled back and down. Just can't see where the bend is...
Looking for a decent truck shop here is a pain. Nothing anywhere near me.

scott123 12-04-2017 08:51 AM

Re: Frame pulling experts
 
The frame out back was driving perfectly and was not doing any where to the tires. I would have never expected it to have been in a crash. When we pulled the body off the passenger side chassis rail was noticeable to the eye.

This one had been hit in the right front pretty hard. The pin broke and the axle had moved. The front horn was pushed in to the center some but there is a obvious bend in the frame between the spring bolts.

Not being the expert the only thing I can think is that with the broken pin the axle slid into an acceptable spot that compensated for the frame issues.

The blazer drove fine and showed no wear on the tires. I'm sure the tie rods and all were overly adjusted at some point.

Best of luck. Old school frame guys are hard to find. Our local guy just retired. He is in his 70's and had a frame machine he built in the 70's. The guy had an eye for matching paint and even a better eye for blending on collision work. It was just about impossible to see where he started and the factory left off.

Best of luck.


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